Individual thermostatic controller for radiators.



E. S. HALSEY.

INDIVIDUAL THERMOSTATIC CONTROLLER FOR RADIATORS.

APPLICATION FILED JULY 21, 1914.

Patent-ed Nov. 7, 1916.

4 SHEET$-SHEET 1.

E. s. HALSEY. INDIVIDUAL THERMOSTATIC CONTROLLER FOR RADIATORS.

APPLICATION FILED JULY 21. 1914.

Patented Nov. 7, 1916.

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WITNESSES:

E. S. HALSEY.

INDIVIDUAL THERMOSTATIC CONTROLLER FOR RADIATORS.

APPLICATION FILED JULY 21. I914.

1 ,2&,36 Patented Nov. 7, .1916.

4 SHEETS-SHEET 3.

gnucuim:

E. S. HALSEY.

INDIVIDUAL THERMOSTATIC CONTROLLER FOR RADIATORS.

APPLICATION FILED JULYZI, I914.

Patented Nov. 7, 1916.

4 SHEETSSHEET 4.

cit/ 571111,

EDWARD S. HALSEY, 0F PHILADELPHIA, PENNSYLVANIA.

INDIVIDUAL THERMOSTATIC CONTROLLER FOR RADIATORS.

aaoaase.

Application filed July 21, 1914. Serial No. 852,160.

T 0 all whom it may concern:

Be it known that I, EDWARD S. HAL'snY,

.a citizen of the UnitedStates, and resident of Philadelphia, in thecounty of Philadelphia and State of Pennsylvania, have invented certainnew and useful Improvements in Individual Therpiostatic Controllers forRadiators, set forth in the following specification and claims.

My present invention relates to steam heating systems and comprisesessentially a means of regulation by which a constant pressure of steamis maintained at all times throughout the flow mains of the system andeach radiator is individually equipped with a direct actingatmospherically influenced thermostatic supply valve of which thethermostat absorbs the energy directly from the room temperature, whichit eXpends individually on its respective valve in a gradual andpositive manner, thereby throttling and limiting the steam fed to theradiator to the proper amount to hold the room temperature constantly ata normal, pre-determined temperature.

Said invention and this application have particular bearing on anintegral thermic valve couple in which a suitable thermic cell is builtdirectly onto and efficiently insulated from the body of the radiatorsupply valve. so that such\c ouple may be installed as a unit.

The object of said invention is to supply a practical, economical andconveniently installed thermic supply valve of a compact and sightlyappearance, providinga pack-' less throttle connection whiclr will beabsolutely tight and of negligible mechanical resistance,'and eflicientmeans for insulating and shielding said thermic elementdrom the hotvalve' and its heated connections including the radiator, when theradiator is sufliciently 'near to require it, and further, to providesuitable means 'of adjusting the thermic element to regulate theefi'ective temperature at which said thermostat is required to act onsaid valve. l

In the accompanying drawings which illustrate my invention similar.numerals and letters refer to, similar parts throughout; the severalviews, in Which- Figure 1., is a front elevation of my Star pattern ofthermic valves, which as a class I have entitled radiostats. Fig. 2,.isa vertical cross-section through the center, showing a fragment ofradiator attached.

Specification of Letters Patent.

' spring of same. tion of the valve body, 8., shown in Fig. 14.

Patented Nov. t, 1916.

Fig. 3., is a diagram of the system including a steam boiler as a sourceof supplywith sensitive pressure regulator, also radiators withradiostats attached thereto. Figs. 4. and 5., are respectively front andrear elevations of my preferred form of radiostat unscrewed from thebody of the valve. Fig.

6., is a vertical cross-section of same through a central line. Figs. 7.and 8-. are modifications thereof. Fig. is a central longitudinalcross-section through a cylindrical modification of my radiostat,adapted to fit underneath a standard sectional radiator.

respectively anend and side elevation on a reduced scale of the lowerportion of a sectional radiator with the radiostat con-' nected and inposition. Figs. 13. and 14. are

respectively, a rear and side elevation of modified form of myradiostat, Fig. 14., showing a fragment of radiator attached. Fig. 15,is a bottom view of same with the valve body, 8., broken 0H. Fig. 16.,is an enlarged sectional view of the special adjusting Fig. 17., is avertical see- Figs. 18. and 19., are respectively a detachedthermostatic mechanism and a packless supply valve to be actuated. bysame through the pipe connection, 43-

. Having described the drawings briefly, a more Perfect understanding ofmy invention may be had from the following detailed description of itsconstruction and operation. In the various types of radiostats shown inthe first two sheetsof drawings the thermostatic expansion cell, 3, in,each case is constituted by a pair of suitably formed flexible metaldiaphragnis sealed about their periphery. This is attached to andsupported by a threaded stem, 21, which in turn is fitted to aconcentric threaded hol in the skeleton cage, 6. Said cage issec'uredto'a composite heat shield by a setof screws arranged aboutits peripherythreaded into four or more "of the legs of said cage. Said heat shieldis constituted by two or. more vertically disposed disks somewhat largerin diameter than the thermostat itself. One

of said disks, (1), is preferably made of a strong non-conductingmaterial, such as socalled asbestos-wood, which is spaced from the otherdisks to permit a free circulation of air between them. In my preferredforms, disk, 2, is made of heavy card board and disk, 32, of metal, forwhich tin plate shield where it is clamped by screws tapped 1 into theterminals of said spider, B. This connecting point is purposely widelyseparated from the points where the thermostat supporting frame, 6, areconnected, whereby to make negligible the heat conduction between saidpoints through said insulating disks. This skeleton spider, B, isstrongly joined to the square headed bonnet, 23, b having a squareorifice through it fitting loosely over-the head of the bonnet like asocket wrench, by means of which the entire working parts of themechanism may be screwed with the bonnet in or out of the valveby usingthe radiostat as a hand wheel.

The Jspid'er is prevented from coming oif the square bonnet head by anumber of beads of solder adherent'tothe bonnet and overhanging thespider, leaving the spider loosely but strongly united to it, givingmechanical strength with low conduction of heat.- Such heat as isconducted through the four slender heat-resistant arms of the spider islargely dissipated by passing through-the circuitous interrupted andwell ventilated'poorly conducting structure be fore the four terminalconnections or clamping points are reached. Thus practically no heat canarrive by conduction from the valve to the thermostat, although veryclosely associated. The multiple vertically disposed heat shieldeffectively-arrests and dissipates practically all radiated heat fromthe closely associated valve and its heated connections including theradiator. So that in spite of its position, after numerous experiments,I have succeeded in contriving a construction in which the thermostat isaffected only by room temperature. Further,

to accomplish this'result, I have limited the metallic valve stem, 9,tov a position back-of the heat: shield and made an insulating ex- 1tension, 10, of a wooden pindriven into a holein the end of said stem.In the structures shownfiin Figs. 1.- to 6., inclusive, I employ aperfectly steam tight, packles's, frictionless connection between thevalve stem and the throttle-within the valve through the means of athin, very flexible metal diaphragm,,18- In these figures, the innersurface of this diaphragm itself acts as the throttle by moving towardand seating on the raised tubular seat, 20. In Figs. 8. and 19.,however, I have chosen to employ. composition disks attached ;to theinside of said diaphragm. For the sake of simplicity, however, I preferto'use the thin flexible dia-' phragm directly against the tubular seatbacked by the felt cushion disk, 19, and the plunger or compressiondisk, 29, back of the padded diaphragm to 'force it onto the seat andinsure a perfectly tight seating contact. This throttle diaph'ragm hasconcentric and radial corrugations to increase itsflexibility and extentof travel, the radial corrugations or grooves materially enhancing theseproperties, also preventing buckling of the diaphragm, as is moreparticularly described and claimed in my U. S. patent application forpipe thermostatic motors filed,

July, 12th., 1909, Serial Number 507070. This dlaphragm is soldered tothe inner edge of bonnet, 23, or otherwise arranged y to make a steamtight partition between the steam cavity in the body of the valve andthe compression disk cavity between the diaphragm and the bonnet. Iprefer to make this compression disk, 29, in the form of a heavy annularweight to deaden the vibrations of the diaphragm disk by virtue of itsinertia, holding the felt pad snugly against the diaphragm.

As a means of increasing the degree of temperature of which thethermostat operates slightly and tolneutralize the natural increase ofdiaphragm resistance which progressively increases with dilation, I havedevised aspecial spring construction which supplies a resistance to thediaphragm expansron of a nearly constant or slightly decreasing tensionwith progressive compression, contrary to the common lawof springs inWhlCh the tension invariably increases at a fixed ratio. withdeflection. I secure this result by the bowed; fiat spring, I, shown inFigs. 6. and 7., and with a modified application in Figs. 13., 14., 15.,and 16. This spring is restrained from elongation by end pivoting yokeclamps, 91. In Fig. 6., this clamp is made adjustable, being constitutedby two end sections or claws slidingly secured in slots, 53, byscrewspenetrating the asbestos-wood disk, 1. In order'to'a-djust thethermostat to its normal working temperature, when the thermostat isinthedesired position, determined by the spring check ring, 30, on thethreaded supporting stud, 21', being lodged against the'thermostatsupporting frame, the adjusting screw,

35, is tightened against the screw holding the lower yoke clip, 91',until the desired working temperature is reached. At any time thereafterthe end tension on said ad justing spring may be partially or entirelyrelieved, thereby lowering the efi'ective actuate s the through themedium of the felt pad, 19, as

eral-degrees by swinging out cam, 37 which is pivoted on the retainingscrew of the.

upper yoke clip, 91. In Fig. 6, the thermostat and spring are shown attheir maxi-'- mum deflection with the throttle disk tightly closedagainst itsport, 20.

In Fig. 7., the thermostat is collapsed and the spring at its limit ofminimum travel, with the valve wide open. The valve construction-shownin this figure is of the bi-port balanced type.

In the modification shown in Fig. 8., instead of having the port seatraised in the form of a tube to meet the disk diaphragm, an accordionbellows form of diaphragm is adapted to extend from the point where itis secured to the bonnet down to the port seat at the other end of thebody. This form of diaphragm is much more expensive than the disk form.The spider, B, in this figure is shown simply as a four legged outriggerinstead of the composite ring form shown in the preceding figures. I

In the cylindrical modification of my composite thermic valve, shownexclusively on the third sheet of drawings, the thermic cell isconstituted by an outer cylindrical shell with a closed end. The inneropening of said shell is sealed by a piston plate, 54,

flexibly united with a solid diaphragm, 55, by means of a multiple ofthinflexible metal diaphragm pairs, 3, of a bellows construction sealedtogether about their peripheries and to a'set of central collars. Thethrust of the internal pressure of volatilization is communicatedthrough aconcentric threaded piston rod to the wooden piston section,10, which in turn presses againstthe metal stem, 9, of the compressiondisk, 29, which disk throttle diaphragm previously described.

The operating temperature of the thermostat may be adjusted by means ofknurled disk nut, 56, which travels on the piston rod to increase ordecrease the tension of the chair spring on the vapor tension within thethermic cell. Access is had'togthis adjusting wheel through four largeperforations in the shell, which perforations also provide freecirculation of air to the surfaces within the shell to increase theeffective surface exposed to the atmospheric convection. Said shellis-supported and insulated from the body of the valve by the woodencylinder, 73, secured to the bonnet by wood screws. This, thermic cellis designed of a proper shape and size to go beneath a standard castiron radiator, from ,which it may be insulated by two paste boardsheets, 2 and 2 with an intervening mitted heat. To support and tofurther insulate the thermic cell from the radiator and shield, I wedgeanother sheet of insulating board, 74, between the thermic cell and thetin plate, 32. I preferably attach as shown in the preceding figures, sothat they may be readily detached for ready inspection or repairs and toenhance the safety the entire working mechanism'to the bonnet,

14., and 15. In this modification which is radically different from thepreceding, the thermic expansion disk, 3, which like the precedingcontains a small quantity ofvolatile liquid, is clamped and restrainedbetween a pair of hinged cast iron grid plates,

-C and E, which are pivoted or hinged together by loose fitting rivets,S and. S, at the top corners, whichpermit the bottom extremities of thegrids to swing freely apart an eighth of an inch or more. The

front grid is supported by being fixed to, a

slender cast iron spider, B,'by four screws, 46, tapped into the fourextremities of the out-riggers constituting said spider. Saidout-riggers are centrally united. in a central split ring or band whichis clamped around the cylindrical outer extremity or branch of thecross-T, N), which forms the trupk of the valve body, 8. This splitcollar is clamped to said body by means of the contracting screw, ,H.Being supported thus the thermostatic expansion forces back the rear orswinging grid, E, which carries a duplex air spaced heat shieldconstituted by insulating plates, 22, which arejoined by three verticalinsulating liners,

JJJ, which are screwed to said grid. This heat shield swinging as a unitwith said grid presses against anti-friction wheel, a

R, pivoted in the extremity of lever, T, which is united to an innerreversed branch, Y, thereof. This lever arrangement is pivoted or hingedby and on a thin metal diaphragm, 100, which allows a free travel of thelever through a wave motion of the diaphragm, which .rocks freely undera slight stress, providing a packless, steam tight, frictionlessconnection between the outer actuating mechanism and the throttle withinthe valve. The inner and outer sections of the throttle lever areclamped together by the screw, 28. The intervening tubular collar, 34,clamps the diaphragm against the inner section of'the lever.Thediaphragm is soldered to the threaded collar or bushing, 42,. andafter all the working parts are in position the guard plate, P, issoldered over the head of said bushing to protect these relativelydelicate parts tension on the thermostat for adjusting and altering theactuating temperature thereof, I have devised the vertical scale bar, F,

attached to the back thermostat gridby means of tie rods, Q. and Q,which are" loosely socketed to permit a slight lateral motion. Betweenthis vertical bar, which. swings with the back grid, I have placed thespeciallyconstructed spring, I, with its end restraining yoke, 91, andattached forked indicator, G. This indicator straddles the scale bar andslides up and down it with said spring-and yoke, to alter the relativeposition and consequent effective tension of said spring mechanism onthe thermostat, proportionate to its distance from the upper hinge ofthe grids.

The scale bar is ordinarily calibrated with the normal temperature of 70degrees at the center of the slide, so that when the spring is manuallyforced to the lowest position the indicator, G, will rest at about 74degrees. And when it is moved to the upper- I most position, it willindicate that the de-v vice-is adjusted towork at about 66 degrees. Theraised nibs, 78, about one fourth of the distance from either end of thespring, which in Figs. 6. and 7., are constituted by screw points, areprovided to preventeither end ofthe spring from being accidentally bentso far below its normal position as to fail to recover itself.

Fig. 18, is a diagrammatical cross section sketch of a thermostaticexpansion cell, 3, of relatively large diameter exerting "its forceagainst an elastic cell of very much smaller diameter, (44), which is.adapted to be filled with a suitable non-volatile fluid andconnected-with a valve shown by Fig. 19, through the medium of ahermetically sealed pipe, 43, in which the bonnet. chamber above thediaphragm is also fluid filled as well as said connecting pipe. Withthis arrangement said thermostat may be located a considerable distancefrom said supply valve and actuate the valve, by its expansion, from I atemperature change of less than two degrees. This may be-accomplished byvirtue of the very much greater effective area of the thermostat inrelation to the working area of the fluid. pressure cell, resulting in agreater internal pressure developed in said cell and acting upon thediaphragm,

yoke connecting the lower and pipe dampers 18, of the valve and itsattached compression and throttle disks, so that with an in.-= ternalpressure of, say, one third of a pound within the thermostat, per squareinch, it is possible to exert a pressure of three or more pounds per.square inch on diaphragm, 18. I

It shouldbe understood that in the several modifications hereindescribed where Y the throttling. is accomplished by oompres- 5 sion' ofthe diaphragm, from the bonnet or outward side thereof against the steampressure and seat withinthewvalve, that, upon reverse action when thepressure from without relaxes, the diaphragm is unseated and 30 restoredto its former position by the internal steam pressure which ismaintained as a constant factor,- and also by the natural spring of thevery thin diaphragm itself, which is preferably from one to threethousandths of an inch in thickness.

- Referring again to Fig. 3., illustrating the completearrangeinent ofmy system, the pressure regulator consists of a damper over a pair ofpulleys having a counterweight, 81, holding the lower draft normallyopen and provided with a water tank, 51,

connected by a flexible hose, 101, below the water line of the boiler.Said tank is provided with an air vent, 41, at the top to permit waterfrom the boiler to enter freely in proportion to the steam pressure,thereby weighting down the front damper and checking the fire in themost sensitive manner upon the slightest excess of pressure above thenormal pressure for which the water tank is set.-

.27 indicates the radiostat connected to radiator 45.

31, indicates the return trap.' Referring again to Fig. 7., it will beseen, that in this modification, I show instead of the throttle,diaphragm as a low friction means of communicating the motion of thethermostat to the throttle, a thin coned fiber washer, 39 (as claimed inmy application, #507071, filed July, 12th., 1909.), one sixty fourths ofan inch in thickness, which may be made of vulcanized fiber, jute boardor similar tough and plastic fiber which may answer the purpose. Thehole through the washer is normally slightly less than that of the valvestem passing through it, but

on account of its thinness and plastic nature while wet, it allows therod to slip back and forth freely with a steam tight joint and istightly secured in position by the'nut, 40, clamping it to the cone studsurrounding the stem.

I am aware that considerable effort has been 'made to devise asuccessful system such as I herein describe. Also to construct asuccessful integral, thermic supply valve for said purpose. But Iam notaware and do not believe that any such device has ever been constructedor used incorporating the several essential elements which I hereindescribe and claim. I claim I 1. In combination with a heating radiatorand the regulating valve thereof, a'thermostat mounted on said valve andconnected thereto to open and close the same in accordance with thetemperature changes, said thermostat being located at one side of thevalve out of the path of heated air currents rising from the valve, anda shield repellant to radiant heat arranged between the thermostat andvalve, whereby the. thermostat is acted upon only by air havingsubstantially the average room temperature and influence of the heatedvalve is substantially ,or support of ventilated skeleton structuremounting said cell and mounted on the valve 'body, arranged to hold thecell at one side of the valve out ofthe path of the heated air currents.rim'ng therefrom, operating connections between the cell and valve foropening and. closing the latter in response to movements of the formercaused by temperature changes, anda shield resistant to radiant heatinterposed between the cell and valve body. y

3. An individual radiator control com-prising in combination a valvebody and valve therein, a thermostatic cell, an outrigger or support of-ventilated skeleton structure mounting said cell and mounted on thevalve body, arranged to hold the cell at one side of the valve out ofthe path of heated air currents rising therefrom, operating. connectionsincluding a motion transmitting member of heat-insulating materialbetween the cell and valve for opening and closing the latter inresponse to movements ,of' the former caused by temperature changes, and

a shield resistant to radiant heat interposed.

between the cell and valve body.

4. In an integral, composite, temperature regulating radiator supplyvalve, aninternally ported valve body; a bonnet closing one side of saidvalve; a non-heat-conducting out-rigger fixed to said bonnet supportinga sensitive, atmospheric, 'thermic cell out to one side from said valveand itsris' ing heat currents; an eflicient radiant heat shield for saidthermic cell carried by said outrigger between the cell and the valve; athrottling disk within said body; and a packless friction eliminatingdevice communi cating the closing pressure from said cell to said diskthrough and by means of a flexible diaphragm 18, hermetically sealedinside of saidbonnet.

5. In an intgeral, composite temperat purpose specified.

regulating radiator valve, an internally ported valve body; a detachablevalve bonnet closing one side of said body; a nonheat-transferringholder carried by said bonnet, a thermostat mounted on said holder outto one side from said valve and its rising heat currents; a throttlingvalve stem from said bonnet in connection with said thermostat bynon-heat-transferring means; and a suitable, eflicientradiant-heat-shieldingmeans interposed between said thermostat and theadjacent heat-radiating surfaces.

6. In a composite valve of the class described, a. suitable atmosphericthermostat close beside and fixed to the body,of said valve by heatresisting means; a non-conducting actuating connection between saidthermostat and a throttle within the valve; a vertical heat shieldconstituted by a multiple of vertical plates one of which at least beingof non-metallic material, said shield being interposed between saidthermostat and valve for the purpose specified.

7. In a composite valve of the class described, a suitable atmosphericthermostat close beside and fixed to the body of said valve by heatresisting means; a non-con ducting actuating connection between saidthermostat and a throttle within the valve; a vertical heat shieldconstituted by a multiple of non-metallic insulating plates spaced fromeach other with an interlaminated metallic plate, said shieldbeinginterposed between said thermostat and valve for the 8. In ,a compositevalve of the class described a body portion; a detachable bonnet formingone side of said body; out-riggers fixed to radiate from said bonnet; anonconducting heat shield concentrically fixed to said out-riggers, orspider; a thermostat arranged concentricallyoutside of said shield; andaconcentric actuating push stemextending through said shield and bonnetfor the purpose specified.

9. In a composite valve of the class described, a valve body; athermostat attached to one side of said body; a vertical heat shieldinterposed between said thermostat and body; a; detachable bonnet forsaid body; a thin flexible metal partition so interposed between-thecavity of said body and said bonnet as to create a secondarycavitywithin and between said flexible par-- tition and said bonnet; athrottling disk carried by said partition on the body side thereof andan actuating stem leading from the other side of said partition throughthe bonnet and heat shield to said thermostat for the purpose specified.

10. In a composite valve of the class described, an atmosphericthermostat fixed close to one side of-the body of said valve;

a detachable bonnet for said body; an'internal cavity in said bonnet; athin metal diaphragm partitioning said bonnet cavity from the interiorcavity of said body; a

raised valve seat within said bodv project ing to the vicinity of; saiddiaphragm a compression head or disk back of 'saiddiai phragm; a cushionpad between saidhead and disk and a concentric thrust rod leading fromsaid disk to the thermostat, by means of which the diaphragm -may besnugly forced to said seat to close said port.

11.'In a composite, valve of the class described, an atmosphericthermostat constituted'of vertically disposed horizontally expandingdiaphragms fixed closebeside the body of said valve; a heat shieldinterposed between said thermostat and body; an actuating connectionbetween said thermostat and valve fan'd'a thin skeleton supporting"tween said thermostat and a throttle within said .valve; a heat shieldof suitable insulating material interposed between said body andthermostat and a set of supporting metal out-riggers branching from saidbody and securing said insulating shield at divergent points and athermostat supporting frame on the other side of said shield secured toit at a multiple of points effectively separated from the said points towhich said nected so as to secure a substantial support supportingout-rigger terminals are conthrough said shield without a materialconduction of heat, 13. In a composite valve of the class described, aradiatorsupply valve; 'an actuating thermostat connected thereto,consisting of a pair of diaphragms sealed together about theirperiphery; a heat shield intervening between said thermostat and valve;a valve stem extending from the throttle within the valve to the back;'of said thermostat; a supporting frame for said thermostat fixedoutside of said heat shield and thermostat having a concentric threadedhole; a concentric threaded supporting stem fixed to said thermostatarranged to be screwed back and forth in said threaded hole by means ofwhich the lateral position of said thermostat may be adjusted byrevo1v--. ing the thermostat and stem to alter the ac-' tuatingtemperature thereof.

14. In a composite valve of the class descri-bed, a radiator supplyvalve; an actuating thermostat connected thereto, consisting of a pairof diaphragms sealed together about their periphery; a heat shieldintervening'between said thermostat and valve;

a valve stem extending from the throttle to the back of the thermostat;a supporting frame for said thermostat fixed outside of said heat shieldand thermostat having a concentric threaded hole; a concentric threadedsupporting stem fixed to said thermostat' arranged to travel back andforth in said threaded hole by means. of which the position of thethermostat 'may be adjusted by revolving the thermostat and stem toalter the actuating temperature 'thereof; and an adjustable check collarfor fixing or determining the normal inward position.

.115. In a thermostatlc temperature regulating mechanism, a sealedthermic cell consisting-of a flexible metal disk diaphragm; a heatdominating valve or contact conn cted to and actuated by said expansionc 11; a spring geared to and restraining the expansive movement-of saidmechanism so constituted and applied as to exert a decreasing resistanceto said expansion as the deflection of said diaphragm and springincreases, tending to balance the natural increasing resistance of thediaphragm.

'16. In a thermostatic temperature regulating mechanism, a sealedthermic cell having an expansion member consisting of a metal diskdiaphragm; a heat dominating valve or contact connecting to and actuated'by said expansion cell; a spring geared to and restraining theexpansive movement of said mechanism consisting of a bowed flat spring,restrained against elongation and having a central traverse tension of acon- 'stant or decreasing degree as it is depressed against its arch forthe purpose specified.

17. In a thermostatic temperature regulating mechanism, a sealed thermiccell having an expansion member consisting of a metal disk diaphragm; aheat dominating valve or contact connecting to and actuated by saidexpansion cell; a spring geared to and restraining the expansivemovement of said mechanism consisting of a bowed flat spring, I,restrained against elongation and having a central traverse tension of aconstant' decreasing degree as it is depressed against its arch; and ameans provided for releasing and adjusting the effective tensionwitnesses this twentieth day of July, 1914.

EDWARD S. HALSEY. Witnesses I. T. Tracer, S. (L-Hussy.

